The invention relates to an apparatus for cleaning an endoscope, and more particularly, to an apparatus for cleaning a distal end of an endoscope which is inserted into coeloma and used therein.
As is well recognized, an endoscope which is used for the medical purpose of obtaining an observation of an affected area within coeloma comprises an elongate flexible tube internally containing an observation and an illumination optical system, each formed of a bundle of optical fibers and which is adapted to be inserted into coeloma, and an operating end which remains outside the coeloma to permit various manual operations. When the distal end of the endoscope is withdrawn from the coeloma after the termination of diagnosis or therapy with the endoscope, it has coeliac fluid, blood and other contaminants on it. Hence, it is necessary to clean and sterilize the distal end of the endoscope which has been inserted into the coeloma in order to permit its repeated use.
By way of Example, FIGS. 1 and 2 show a side elevation partly in section and a plan view, respectively, of a conventional cleaning apparatus which is used to clean the distal end of a used endoscope. Referring to these Figures, cleaning apparatus 1 comprises cylindrical frame 2, to the top of which is secured rinse vessel 3 in the form of a hollow cylinder having bottom plate 3a. Hollow drive shaft 4 extends through bottom plate 3a in alignment with the axis of vessel 3, and a pair of spray heads 8a, 8b have one end joined together and are secured thereat to the top of drive shaft 4 and have their free end extending toward cylindrical wall 3b of rinse vessel 3 at an upper and a lower level, respectively. A plurality of circumferentially spaced and radially extending support members 6 have one end fixed to the inner surface of cylindrical wall 3b of rinse vessel 3 and have another end extending radially inward in a plane which is located intermediate spray heads 8a, 8b. Drive shaft 4 is adapted to be driven for rotation by a motor, not shown, and internally houses liquid feed pipe 5 through which a cleaning liquid such as water, a detergent solution or a sterilizing solution is supplied to spray heads 8a, 8b.
A plurality of circular spray apertures 9a, 9b are formed in spray plates 10a, 10b which are fitted into the bottom of upper spray head 8a and into the top of lower spray head 8b, respectively. The radially inner end of upper spray head 8a is formed into a cylindrical shape so as to be pivotally mounted on base 7. When a portion of the endoscope, indicated in phantom by numeral 20, which has been inserted into the coeloma is to be mounted on support members 6, upper spray head can be moved to position 8aA shown in phantom in FIG. 2. Support members 6 comprise metal wires having a plurality of radially spaced depressions 6a formed therein, and the portion 20 of the endoscope which is to be cleaned is spirally coiled to be received in these depressions 6a. In this manner, depressions 6a serve to locate the portion 20 of the distal end in a cleaning position. A liquid drain shown by numeral 11 is formed in bottom plate 3a of rinse vessel 3.
In operation, the portion 20 of the endoscope is placed on and supported by depressions 6a of support members 6. Subsequently, cleaning water is supplied to spray heads 8a, 8b through feed pipe 5, and thence directed to the upper and lower surfaces of the portion 20 through spray apertures 9a, 9b, thus cleaning the outer surface of endoscope portion 20. At the same time, drive shaft 4 is driven for rotation to cause heads 8a, 8b to rotate about the axis of shaft 4. One revolution of heads 8a, 8b is effective to rinse the portion 20 with water over its entire length. When the water rinsing operation is completed, a sterilizing solution is fed to spray heads 8a, 8b through feed pipe 5, sterilizing the portion 20 in the same manner as in the water rinse operation.
When apparatus 1 is used, the upper spray head 8a interferes with the placement in and removal from apparatus 1 of the portion 20 of the endoscope. Hence, head 8a is moved to position 8aA shown in phantom line in FIG. 2, and after the portion 20 is placed on depressions 6a of support members 6, the upper head 8a is returned to its original position. It will be seen that such operation and the required construction therefor are undesirable. In addition, there is an apparatus known which is provided with a plurality of pairs of spray heads 8a, 8b in order to increase the cleaning efficiency. It is apparent that the placement and removal of the portion 20 of the endoscope is still more troublesome with such an apparatus.
Spray plates 10a, 10b of spray heads 8a, 8b are formed with a multiplicity of circular spray apertures 9a, 9b, and it is customary that the diameter of these apertures 9a, 9b be reduced in order to increase the injection speed of the cleaning liquid, and to provide an increased spacing between these apertures. This results in the problem that apertures 9a, 9b are liable to be plugged, and the increased spacing between these apertures disadvantageously causes non-uniform cleaning of the endoscope portion 20.
When the sterilization process follows the water rinse operation, any residue of cleaning water which remains within feed pipe 5 and spray heads 8a, 8b may dilute the sterilizing liquid, either preventing an effective sterilization effect or requiring an increased amount of sterilizing solution.